[Study on the relationship between age-related hearing loss and cognitive impairment].

Objective: To investigate the correlation between age-related hearing loss and cognitive impairment. Methods: 201 elderly patients, who were admitted to the Department of Otorhinolaryngology of Peking University People's Hospital from March 1, 2017 to March 31, 2017, were evaluated with hearing screening and the Montreal Cognitive Assessment Scale. Among them, 101 were female and 100 were male, aged 60-90 years old. Taking the cognitive level as the dependent variable, and taking the age, sex, education, occupation, marital status, residence, and average hearing loss (average hearing threshold of 500, 1 000, 2 000, and 4 000 Hz), as well as the length of conscious hearing loss as the independent variables, the single factor analysis and multivariate linear regression analysis were used to screen the main factors affecting the cognitive level of the elderly. Results: Of the 201 elderly patients, 39 had normal hearing, 65 had mild hearing loss, 80 had moderate hearing loss, 16 had severe hearing loss, and 1 had profound hearing loss. The average degree of hearing loss was the influencing factor of cognitive impairment, and it mainly affected the directional force and abstract ability in the cognitive domains (P<0.05); The age, self-reported hearing loss, years of education, marital status, past ear diseases, and hypertension were relatively independent factors that affected the cognitive level(P<0.05). Conclusions: Age-related hearing loss is the risk factor for the cognitive impairment, especially for abstraction and orientation, in the elderly. The self-reported hearing loss is an independent risk factor for cognitive impairment.

[Analysis of nystagmus and medical history of 121 patients positive with positional test].

Objective: To observe the characteristics of positional nystagmus and clinical profile of patients with positive positional test, and to explore its possible pathogenesis.Method: One hundred and twenty-one patients with positive positional test in the vestibular function examination were enrolled in the Peking University International Hospital from January to June in 2017. According to the 2017 BPPV guidelines, patients with test positive positional nystagmus were divided into two groups: definite BPPV and the controversial syndrome. Analyses of gender, age and characteristics of nystagmus, with or without recurrent dizziness, headache, and motion sickness were undertaken between the two groups, as well as response to the repositioning maneuver. Result: Of the total 121 cases, 49 cases were diagnosed as definite BPPV, accounting for 40.5%, 72 cases as controversial syndrome, accounting for 59.5%. The proportion of women in the two group was 76.2% and 78.9%, respectively. The average age of definite BPPV and the controversial syndrome was 51.2±16.8 and 51.3±15.7, respectively.There were significant differences in nystagmus duration, spontaneous nystagmus and nystagmus after headshaking between the two groups by chi square test(P<0.01). The mean intensity of horizontal and vertical nystagmus in posterior semicircular canal BPPV was(10.2±7.4) °/s and(36.6±17.5) °/respectively. And the mean intensity of nystagmus in the strong and weak side in horizontal semicircular canal BPPV was(40.8±25.1) °/s and(20.7±11.1) °/respectively. The intensity of horizontal and vertical nystagmus of the controversial syndrome group was(7.2±7.7) °/s and(7.2±4.3) °/s respectively. The incidence of headache in the controversial syndrome group was significantly higher than that in the BPPV group, P=0.013. According to the guidelines, patients were evaluated one day after the initial treatment. The cure rate and effective rate of the definite BPPV group was 75%(36/48) and 87.5%(42/48),and was 0 and 30.4% in the controversial syndrome group respectively. Conclusion: The patients in controversial syndrome group have a preponderance of exhibiting positive nystagmus during positional test. Nystagmus were usually of low velocity and sustained. Most of these cases presented spontaneous nystagmus and headshaking induced nystagmus, as well as headache and lacunar infarctions in history, and the response to the repositioning maneuver were often poor. It may be related to vestibular migraine and central nervous system. The diagnosis of BPPV must be prudent.Both characteristics of nystagmus and medical history should be carefully analyzed to avoid overdiagnosis.

Controlled state transfer in a Heisenberg spin chain by periodic drives.

The spin chain is a system that has been widely studied for its quantum phase transition. It also holds potential for practical application in quantum information, including quantum communication and quantum computation. In this paper, we propose a scheme for conditional state transfer in a Heisenberg XXZ spin chain. In our scheme, the absence or presence of a periodic driving potential results in either a perfect state transfer between the input and output ports, or a complete blockade at the input port. This scheme is formalized by deriving an analytical expression of the effective Hamiltonian for the spin chain subject to a periodic driving field in the high-frequency limit. The influence of the derivation of the optimal parameter on the performance of the state transfer is also examined, showing the robustness of the spin chain for state transfer. In addition, the collective decoherence effect on the fidelity of state transfer is discussed. The proposed scheme paves the way for the realization of integrated quantum logic elements, and may find application in quantum information processing.